The field of the invention generally relates to refrigeration devices that have a defrost cycle, and more particularly relates to drain pan apparatus for such devices.
As is well known, refrigeration devices generally have a refrigeration loop including a compressor, condenser, expansion valve, and evaporator. It is also well known that ice or frost tends to form on the outside of the evaporator, and such ice interferes with the thermal transfer of heat to the evaporator. Accordingly, in order to remove the ice, many refrigerators have a periodic defrost cycle wherein an electric heating element proximate to the evaporator is activated during an off cycle of the compressor. The water formed by melting the ice then flows through a drain hose to a drain pan which typically is positioned on top of the condenser coils at the bottom of the refrigerator.
Water in the drain pan evaporates at a long-term rate that is faster than the inflowing rate of new defrost water, so the drain pan never needs emptying during normal operation. Nevertheless, there is a general requirement that the drain pan not be rigidly affixed in place because there are occasions when it is desirable to remove the drain pan. For example, if the refrigerator is being moved from one location to another, the drain pan is generally removed because water in the drain pan could spill as a result of the motion; such spilling would be inevitable if the refrigerator was tipped onto a dolly, as is often the case. Also, it is desirable to clean the condenser periodically, and the normal procedure is to remove a lower front grill and then remove the drain pan to expose the condenser coils underneath.
Prior art drain pans sit loosely on top of the condenser. This arrangement has the advantage of not requiring any critical alignment, and therefore the drain pans have been relatively easy to remove and replace even though they are awkwardly positioned close to the floor. However, refrigerators tend to have some vibration caused by the compressor, and such vibration commonly results in the drain pan rattling.